CF444C. DZY Loves Colors[线段树 区间]
DZY loves colors, and he enjoys painting.
On a colorful day, DZY gets a colorful ribbon, which consists of n units (they are numbered from 1 to n from left to right). The color of the i-th unit of the ribbon is i at first. It is colorful enough, but we still consider that the colorfulness of each unit is 0 at first.
DZY loves painting, we know. He takes up a paintbrush with color x and uses it to draw a line on the ribbon. In such a case some contiguous units are painted. Imagine that the color of unit i currently is y. When it is painted by this paintbrush, the color of the unit becomes x, and the colorfulness of the unit increases by |x - y|.
DZY wants to perform m operations, each operation can be one of the following:
- Paint all the units with numbers between l and r (both inclusive) with color x.
- Ask the sum of colorfulness of the units between l and r (both inclusive).
Can you help DZY?
The first line contains two space-separated integers n, m (1 ≤ n, m ≤ 105).
Each of the next m lines begins with a integer type (1 ≤ type ≤ 2), which represents the type of this operation.
If type = 1, there will be 3 more integers l, r, x (1 ≤ l ≤ r ≤ n; 1 ≤ x ≤ 108) in this line, describing an operation 1.
If type = 2, there will be 2 more integers l, r (1 ≤ l ≤ r ≤ n) in this line, describing an operation 2.
For each operation 2, print a line containing the answer — sum of colorfulness.
3 3
1 1 2 4
1 2 3 5
2 1 3
8
3 4
1 1 3 4
2 1 1
2 2 2
2 3 3
3
2
1
10 6
1 1 5 3
1 2 7 9
1 10 10 11
1 3 8 12
1 1 10 3
2 1 10
129
In the first sample, the color of each unit is initially [1, 2, 3], and the colorfulness is [0, 0, 0].
After the first operation, colors become [4, 4, 3], colorfulness become [3, 2, 0].
After the second operation, colors become [4, 5, 5], colorfulness become [3, 3, 2].
So the answer to the only operation of type 2 is 8.
题意:区间修改颜色,colorfulness+=颜色差的绝对值,区间查询colorfulness
线段树区间更新和区间查询
col记录颜色,0说明颜色不同;sum是colorfulness;lazy记录增量(colorfulness的增量)
更新的时候遇到相同颜色的被包含的区间直接更新,否则下传标记更新孩子然后合并
#include <iostream> #include <cstdio> #include <algorithm> #include <cstring> #define m ((l+r)>>1) #define lson o<<1,l,m #define rson o<<1|1,m+1,r #define lc o<<1 #define rc o<<1|1 using namespace std; typedef long long ll; const int N=5e5+5,INF=2e9+5; inline int read(){ char c=getchar();int x=0,f=1; while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();} while(c>='0'&&c<='9'){x=x*10+c-'0';c=getchar();} return x*f; } int n,q,op,ql,qr,x; struct node{ ll sum,lazy,col; }t[N<<1]; void merge(int o){ t[o].col=t[lc].col!=t[rc].col?0:t[lc].col; t[o].sum=t[lc].sum+t[rc].sum; } void build(int o,int l,int r){ if(l==r) t[o].col=l; else{ build(lson); build(rson); } } void pushDown(int o,int len){ if(t[o].col){ t[lc].col=t[rc].col=t[o].col; t[lc].lazy+=t[o].lazy; t[rc].lazy+=t[o].lazy; t[lc].sum+=t[o].lazy*(len-(len>>1)); t[rc].sum+=t[o].lazy*(len>>1); t[o].col=t[o].lazy=0; } } void update(int o,int l,int r,int ql,int qr,ll v){//printf("update %d %d %d\n",o,l,r); if(ql<=l&&r<=qr&&t[o].col){ t[o].sum+=(r-l+1)*abs(v-t[o].col); t[o].lazy+=abs(v-t[o].col); t[o].col=v; }else{ pushDown(o,r-l+1); if(ql<=m) update(lson,ql,qr,v); if(m<qr) update(rson,ql,qr,v); merge(o); } } ll query(int o,int l,int r,int ql,int qr){ if(ql<=l&&r<=qr) return t[o].sum; else{ pushDown(o,r-l+1); ll ans=0; if(ql<=m) ans+=query(lson,ql,qr); if(m<qr) ans+=query(rson,ql,qr); return ans; } } int main(){ n=read();q=read(); build(1,1,n); for(int i=1;i<=q;i++){ op=read();ql=read();qr=read(); if(op==1){x=read();update(1,1,n,ql,qr,x);} else printf("%I64d \n",query(1,1,n,ql,qr)); } }